Gilead Initiates Phase II HIV Trial for Once-Daily Regimen

Gilead Sciences has begun enrollment in a Phase II trial of its investigational integrase-based, single-tablet, once-daily regimen of elvitegravir, GS 9350 and Truvada (emtricitabine 200 mg/tenofovir disoproxil fumarate 300 mg) for the treatment of HIV-1 infection. GS 9350 is being developed as a pharmacoenhancing or “boosting” agent to increase blood levels and allow once-daily dosing for certain medicines, including the company’s elvitegravir. The study is designed to evaluate the safety and efficacy of the regimen compared to once-daily Atripla (efavirenz 600 mg/emtricitabine 200 mg/tenofovir disoproxil fumarate 300 mg). The study will enroll 75 HIV-1 infected, antiretroviral treatment-naïve adults across 50 sites in the U.S.

“The initiation of this Phase II study is an important milestone in the development of our integrase-based, single-tablet, once-daily regimen for HIV,” said Norbert Bischofberger, Ph.D., executive vice president, R&D and chief scientific officer, Gilead Sciences. “The single-dose regimen of Atripla has become the standard of care for many patients, particularly those new to therapy. If proven safe and effective, this new single-tablet regimen has the potential to provide an important alternative for them.”

Gilead is also studying GS 9350 as a stand-alone boosting agent for other antiretrovirals, in particular, protease inhibitors. Gilead plans to initiate a Phase II trial evaluating the safety and efficacy of GS 9350-boosted atazanavir compared to ritonavir-boosted atazanavir each in combination with Truvada. Ritonavir is currently the only boosting agent available for HIV therapy.